Abundant hemoptysis revealing an aneurysm of an aberrant systemic artery to the left lower pulmonary lobe: A case report

Pulmonary sequestration (PS) is a congenital anomaly characterized by a lung region that is isolated from its normal bronchial and vascular connections. It typically receives blood supply from an aberrant systemic artery. An aneurysm of that aberrant artery is extremely rare. We report the case of a 55-year-old female patient who was incidentally diagnosed with intralobar PS after experiencing severe hemoptysis. The diagnosis was set by a chest contrast-enhanced computed tomography (CT), which also revealed an aneurysm of the aberrant systemic artery. A left lower lobectomy was successfully performed which confirmed the diagnosis. PS is characterized by a mass of lung tissue that lacks connection to the normal bronchial tree and is supplied with blood from the systemic circulation. There are 2 primary types: intralobar (ILS), located within a lung lobe, and extralobar (ELS), situated outside the lobes with abnormal vascular connections typically originating from the thoracic or abdominal aorta. In ILS, drainage usually occurs through pulmonary veins, whereas ELS often drains via the azygos or portal venous system. CT and magnetic resonance imaging (MRI) are preferred for diagnosing PS. They can also reveal complications such as an aneurysm of the aberrant artery, as in our case. PS is a rare yet significant anomaly to consider in cases of recurrent pneumonia or persistent consolidative opacities, especially when involving the lower lobe of the left lung. CT and MRI are highly valuable for pinpointing the lesion and identifying the feeder blood vessel associated with it.